High resolution analytical scale electrophoresis has become a common tool in the biochemistry laboratory. However, the retention of high resolution of the preparative scale has ben difficult if not impossible. Recently, a novel device has been designed and fabricated which offers potential for high resolution separation of biological macromolecules by electrophoresis on the preparative scale. This funnel-shaped electrophoretic device makes possible the separation of proteins, polysaccharides, and nucleic acids in an inert matrix such as polyacrylamide or agarose. The geometry of the funnel apparatus provides a large surface area for heat dissipation and high sample load. With this new system, macromolecules separate into discrete bands, but then concentrate as they migrate down the gel until they exit at the collection port where a stream of flowing buffer sweeps each resolved component into a conventional collection device. In this application, we propose to further refine the funnel electrophoretic device (FED) and demonstrate its general utility. The system will be used for preparative isolation of the isoforms greater than 6) of apolipoprotein(a) (Mr = 400- 750 kD), a protein whose blood concentration has been highly associated with coronary artery disease. Development of the funnel electrophoretic device could have significant, positive impact on biomedical research by providing a new separation technology which affords the combined advantages of low cost, high resolution, and high recovery.